The present disclosure is generally directed to semiconductors of the formulas/structures as illustrated herein, and processes of preparation and uses thereof. More specifically, the present disclosure in embodiments is directed to novel classes of substituted aromatic vinyl-based thiophene semiconductors of the formulas as illustrated herein which are believed to be more stable than, for example, acene-based semiconducting materials. These semiconducting materials can be dissolved or blended in a polymer binder for fabricating uniform thin films which can be selected as semiconductors for TFTs. Accordingly, in embodiments it is believed that the dissolved semiconductor molecules can crystallize out and form a continuous highly ordered semiconducting film to provide excellent TFT performance characteristics, such as efficient field effect charge carrier transport. In embodiments, the new semiconducting materials can be selected as semiconductors for thin-film transistors, and also which can be selected as solution processable and substantially stable channel semiconductors in organic electronic devices, such as thin film transistors, and which devices can be generated by economical solution processes, and which electronic devices are stable in air, that is do not substantially degrade over a period of time when exposed to oxygen.
There are desired electronic devices, such as thin film transistors, TFTs, fabricated with a semiconductor of the formulas as illustrated herein, and which semiconductors possess excellent solvent solubility, and which can be solution processable; and wherein these devices possess mechanical durability and structural flexibility characteristics which are desirable for fabricating flexible TFTs on a number of substrates, such as plastic substrates. Flexible TFTs enable the design of electronic devices with structural flexibility and mechanical durability characteristics. The use of plastic substrates together with the semiconductor of the formulas as illustrated herein can transform the traditionally rigid silicon TFT into a mechanically more durable and structurally flexible TFT design. This can be of particular value to large area devices such as large area image sensors, electronic paper, and other display media. Also, the selection of the semiconductors of the formulas as illustrated herein possess in embodiments extended conjugation for integrated circuit logic elements for low end microelectronics, such as smart cards, radio frequency identification (RFID) tags, and memory/storage devices, and enhance their mechanical durability, and thus their useful life span.
A number of semiconductor materials are not, it is believed, stable when exposed to air as they become oxidatively doped by ambient oxygen resulting in increased conductivity. The result is large off current and thus a low current on/off ratio for the devices fabricated from these materials. Accordingly, with many of these materials, rigorous precautions are usually undertaken during materials processing and device fabrication to exclude environmental oxygen to avoid or minimize oxidative doping. These precautionary measures increase the cost of manufacturing therefore offsetting the appeal of certain semiconductor TFTs as an economical alternative to amorphous silicon technology, particularly for large area devices. These and other disadvantages are avoided or minimized in embodiments of the present disclosure.